M101 - Pinwheel Galaxy
Widefield SN2011fe

M101 - Pinwheel Galaxy
Widefield SN2011fe: M101 is a nice face-on spiral galaxy in the constellation Ursa Major. It is interesting in that it is asymmetrical and physically much larger than the Milky Way. Numerous star forming regions can be seen in the spiral arms.

Messier: 101
NGC: 5457
Right Ascension: 14h 3.2m
Declination: 54° 21'
Apparent Magnitude: 7.7

Date: January 2012
Equipment:
Mount: Losmandy G-11 with Gemini 2
Telescope: Orion ED80T CF apo refractor
Televue 0.8x Field Flattener (53 mm from focal plane)
Camera: SBIG ST-10XE
Guiding ST-80; DSI; PHD

Exposure:
L: 6x10 minutes, binned 1x1
R:5x5 G:5x5 B:4x5minutes, binned 2x2
The camera was at -35°C.

Processing Notes: Data acquisition with CCDSoft. Reduced and aligned in CCDStack. Subs combined in Sigma Beta. Arcsine stretch import of L into Photoshop. Adjusted curves and levels. Increased contrast via a highpass filter overlay layer. Slight blur on the dim areas and sharpening overall. Minimize filter on the stars. RGB combined in AstroArt at 1:1.02:1.65 ratio. Adjusted curves and levels, and reduced noise of RGB. L was combined with RGB in Photoshop.
Scale: ~3.6"/pixel

Links to images of this object on other sites:
http://antwrp.gsfc.nasa.gov/apod/ap090414.html
http://www.jthommes.com/Astro/M101C.htm

Additional Comments: This image was created from several nights of data. Often as a last minute addition to the nights observing as an "extra" target right before dawn. Note the "extra" blue star in the galaxy. Supernova 2011fe is fading now but still the 4th brightest in the sky. An image from the 16" scope is found here: http://www.fortlewis.edu/observatory/image_detail.asp?ID=218

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